Generally, for anticancer drugs, antibiotics, blood products, and lyophilized preparations that are put into containers such as medical fluid bags or vials and the like, there are the problems of poor stability and reduced medicinal efficacy when these products are stored in liquid form. For these reasons, medical institutions such as hospitals have conventionally dealt with this by liquefying these preparations immediately before use, and using them in such ways as intravenous drips. The tasks required to perform this conventionally have involved filling a syringe fitted with a sharp needle with a solution or the like, then thrusting the needle into the rubber plug body of a medicine bag or similar.
Furthermore, when mixing different medical fluids from a three-way stopcock fitted in the middle of a solution-feeding line of an infusion or blood transfusion kit, or, conversely, when collecting medical fluids, or similar, while performing an infusion or blood transfusion for a patient, there are always the tasks of detaching and attaching needles to the main body of the syringe, and using sharp needles for this is accompanied with the risks of accidental needle jabs and medical fluid contamination.
Moreover, synthetic rubbers such as isoprene rubber are used for almost all the plug bodies for these medical fluids, and contact between these and the medical fluids can cause problems of medical fluid contamination due to the elution of additives, so that contact between the plug and the medical fluid is currently avoided by providing a plastic film between these plug bodies and medical fluids. Further, conceivable methods for providing these plastic films include, for example, methods in which fluorine-based resins or the like are laminated on the surface that comes in contact with the medical fluid.
Various contrivances are used in ways intended to solve these problems, such as using adapters or communicating devices such as linking tubes to connect syringes fitted with obtuse cannulas to vials or the like, and then infusing or drawing out the medical fluids.
For example, PCT (WO) H3-504571 (1991) discloses mainly a slitted infusion area into which an obtuse cannula can be inserted repeatedly.
Furthermore, JP H7-75663A (1995) discloses mainly a method of preventing medical fluid contact by applying film to a slitted plug body. Further, at the opening of the container, a rubber plug body is used that is provided with a pre-perforated penetration hole, with this penetration hole enabling approximately 1-mm diameter metal needles to pass through the rubber plug body, and being small enough not to be easily distinguished from the surface by the naked eye. When not yet punctured by a cannula, the plug stays in a blocking condition due to self-sealing of the rubber, and when punctured by a cannula, the surface of the punctured hole adheres to the outer periphery of the cannula due to self-sealing of the rubber.
However, in the method disclosed in PCT (WO) 3-504571 (1991), a special-purpose cannula is necessary in order to allow insertion through the sealing materials. Further, there is no mention of the possibility of using ordinary syringes. Therefore, for infusion or blood transfusion kits requiring three-way mixed injection openings, there exists the potential problem of being unable to perform mixing injections.
Moreover, as no measures are implemented in regard to medical fluid contact, the issue of avoiding contact between the plug body and the medical fluids is unresolved.
On the other hand, JP H7-75663A (1995) has the problem that, although suitable for the insertion of needles with comparatively sharp ends, it is unsuitable for insertion bodies with a flat-surface end such as a syringe luer connector. This is because a large penetration resistance is required to pass through the film at the time of insertion.
Furthermore, there is also the problem that, although the pore surface can adhere to the outer periphery of the cannula due to the self-adhesiveness of the rubber, it is difficult to ensure that inserted cannulas can be maintained stably without wobbling movements.
Moreover, there is no consistency in the way the film ruptures when insertion bodies are inserted, which entails the risk, depending on the way it ruptures, of pieces of ruptured film falling into the medical fluids and causing contamination of the medical fluids.
It is an object of the present invention to solve the problems above by providing a plug body for a medical fluid container, with which contact between plugs and medical fluids can be prevented, and that can be used with insertion bodies with obtuse tips.